The need for effectively barricading an entry door from within is notoriously well known as is the relative ineffectiveness of known systems and devices for achieving this end. For example, in regions (such as some urban areas) in which the crime rate is sufficiently high, virtually every household is provided with a plurality of locks and related devices operated simultaneously on each entrance door to undertake to establish a barricade which will prevent all but the most determined attempts at unauthorized entry. Typically, one or more dead bolt or other key/latch-operated locks are positioned on a door for parallel operation, often in conjunction with bolt operated supplementary devices and/or devices (such as the well-known "chain lock") which permit limited opening of a door before becoming effective.
Those skilled in the security arts are well aware of the draw backs of all these devices, most particularly, their vulnerability to simple brute force unauthorized entry attempts. That is, a sufficiently heavy inwardly directed blow to an entry door will result in ripping the locks and related devices from the door and/or the door frame because the barricade system is only as strong as the cumulative effect of the fastening devices, typically wood screws, in the door and door frame.
It will therefore be appreciated that it would be highly desirable to provide an entry door barricade system that does not suffer from this basic vulnerability to brute force unauthorized entry, and it is to this end that the present invention is directed.